1. Field of the Invention
This invention relates to an ink jet head. More particularly, it is concerned with an ink jet head for producing droplets of recording ink used in a so-called "ink jet recording system".
2. Description of the Prior Art
The ink jet head to be adopted in the ink jet recording system is generally provided with a micro-sized ink discharging port (or orifice), an ink flow path, and an ink discharging pressure generating section provided in one part of the ink path.
As a method for fabricating such ink jet head, there is known one, for example, in which a very fine groove or grooves are formed in a glass or metal plate by cutting or etching, and then the plate having the groove or grooves formed therein is joined with an appropriate cover plate, thereby constructing the ink flow path.
When the ink jet head is fabricated by such conventional method, however, there are accompanying disadvantages such as strain occurring in the ink path due to a difference in the rate of etching making it difficult for the ink flow path to obtain a constant liquid flow resistance with the result being that fluctuations or irregularities tend to readily appear in the ink discharging characteristics from the finished ink jet head, or the plate tends to readily bring about breakage or cracks when cutting, resulting in poor yield in the fabrication, or, in the case of etching, an increased number of process steps would cause rise in the manufacturing cost. In addition, other common disadvantages in the conventional methods are that the grooved plate having the grooves which grooves are to be the ink flow paths are difficult to accurately join with the cover plate, on which various driving elements such as piezo-electric elements, heat generating elements, etc. are provided to generate energy to act on the ink, hence these conventional methods failed to provide for mass-production of ink jet heads. It has, therefore, been earnestly desired that ink jet heads free from these disadvantages are developed.